StephaneL stated it correctly.
JWs are not to even offer a greeting to a DF'd or DA'd person, but when that person is a family member who resides within the same home, then WT stipulates there be minimal interaction and certainly no discussion of 'spiritual' matters.
If the df'd family member does not live in the same home, there is to be no interaction except for when family business is necessary.
When a family member lives in the home, I've heard where some JW families have required the df'd person to eat in another room or at a different time as that person was not permitted to eat with other JW family members. I also understand some parents of a df'd child, have required that child to move-out once reaching 18 years of age (or other age of adulthood applicable to that country).
Often, a person does not need to be df'd to be treated as such as many JWs will provide that treatment to anyone who no longer attends meetings.